Sodium Metabisulfite will be mixed with water to create a first solution at 30% in a make up tank (preparation tank + mixer/stirrer) and after that will be deposited in a storage tank of 12 hours autonomy (it's a batch system), this solution will be dosing to the process not before pass through a post-dilution system (static mixer + water) that will make final solution has 10% of concentration.
The environmental conditions are:
Humidity is around 70-90%
Temperature range: 1 °C - 15 °C
Altitude: 4000 m.a.l.s
Sodium Metabisulfite contains 65% of SO2 available. When Sodium Metabisulfite get in contact with air becomes oxidize (loss part of its SO2 available) Due to its hygroscopic properties this powder absorb the moisture contains in the air quickly.
The water they will use is demineralized. The reaction of Sodium metabisulfite and water is rule by the following:
Na2S2O5 + H2O --> 2NaHSO3
NaHSO3 = Sodium Bisulfite.
However after reading about this chemical it looks like a certain amount of SO2 is released. The amount of SO2 released depends on temperature, ph, and the % concentration.
As Na2S2O5 price pls feel free to contact firstname.lastname@example.org